Specimens of Ulva Linnaeus and
Enteromorpha Link (Ulvales, Ulvophyceae, Chlorophyta)
were collected from 12 sites in eastern Australia and identified to species
level on the basis of morphological characters described in the major
Australian study of Womersley (1984). The species recognised were
Ulva australis Areschoug,
U. lactuca Linnaeus, U. fasciata
Delile, Enteromorpha compressa (Linnaeus) Greville,
E. flexuosa (Wulfen ex Roth) J.Agardh and
E. intestinalis (Linnaeus) Link. Species placement
within the genera Ulva and
Enteromorpha is problematic and features of DNA were
examined in order to assess their potential use as characters in species
determinations. Analyses were conducted on sequence data derived from the
internal transcribed spacer region ITS2, and the 5.8S gene. Groupings of the
12 isolates based on DNA analyses do not correlate with the species identified
using morphology nor with the two genera. Further work is required before
authoritative conclusions can be reached regarding the significance of
morphological plasticity in determination of differences within and between
Ulva and Enteromorpha species;
nevertheless, DNA studies may provide a backbone of characters upon which to
base such a study.